The problem of evil is one of the best and most debated philosophical arguments against the existence of god. Actually in my opinion, it is the best argument ever! A modern version of this argumet is follows something like this: Let, God be defined as an omnipotent, omniscient, omnibenevolent, ontologically basic, non-contingent, disembodied mental entity.

1. If god is Omnibenevolent, he would want to prevent evil.

2. If god is omniscient he would know every possible way in which evil may occur.

3. If god is omnipotent then he would act in every possible way in order to prevent evil from manifesting in every possible way.

4. God is non-contingent which means god is either necessary (necessarily true) or impossible (necessarily false).

categorical mistake. if we redefine 'evil' in relation with our ethical existence,considering our suffering and existence of evil is only a test for given ethical life, then there is nothing contradiction; so as to the evil(or suffering) is a only the distance away from God.